Tailored Intraoperative MRI Strategies in High-Grade Glioma Surgery: A Machine Learning-Based Radiomics Model Highlights Selective Benefits.

BACKGROUND AND OBJECTIVES: In high-grade glioma (HGG) surgery, intraoperative MRI (iMRI) has traditionally been the gold standard for maximizing tumor resection and improving patient outcomes. However, recent Level 1 evidence juxtaposes the efficacy of iMRI and 5-aminolevulinic acid (5-ALA), questioning the continued justification of iMRI because of its associated costs and extended surgical duration. Nonetheless, drawing from our clinical observations, we postulated that a subset of intricate HGGs may continue to benefit from the adjunctive application of iMRI. METHODS: In a prospective study of 73 patients with HGG, 5-ALA was the primary technique for tumor delineation, complemented by iMRI to detect residual contrast-enhanced regions. Suboptimal 5-ALA efficacy was defined when (1) iMRI detected contrast-enhanced remnants despite 5-ALA's indication of a gross total resection or (2) surgeons observed residual fluorescence, contrary to iMRI findings. Radiomic features from preoperative MRIs were extracted using a U2-Net deep learning algorithm. Binary logistic regression was then used to predict compromised 5-ALA performance. RESULTS: Resections guided solely by 5-ALA achieved an average removal of 93.14% of contrast-enhancing tumors. This efficacy increased to 97% with iMRI integration, albeit not statistically significant. Notably, for tumors with suboptimal 5-ALA performance, iMRI's inclusion significantly improved resection outcomes (P-value: .00013). The developed deep learning-based model accurately pinpointed these scenarios, and when enriched with radiomic parameters, showcased high predictive accuracy, as indicated by a Nagelkerke R2 of 0.565 and a receiver operating characteristic of 0.901. CONCLUSION: Our machine learning-driven radiomics approach predicts scenarios where 5-ALA alone may be suboptimal in HGG surgery compared with its combined use with iMRI. Although 5-ALA typically yields favorable results, our analyses reveal that HGGs characterized by significant volume, complex morphology, and left-sided location compromise the effectiveness of resections relying exclusively on 5-ALA. For these intricate cases, we advocate for the continued relevance of iMRI.

Frequency and characteristics of bacterial and viral low-grade infections of the intervertebral discs: a prospective, observational study.

STUDY DESIGN: Monocentric, prospective, observational study. OBJECTIVE: The clinical relevance of bacterial colonization of intervertebral discs is controversial. This study aimed to determine a possible relationship between bacterial and viral colonization and low-grade infection of the discs. METHODS: We investigated 447 disc samples from 392 patients. Microbiological culture was used to examine the samples for bacterial growth, polymerase chain reaction (PCR) was used for detection of herpes simplex virus types 1 and 2 (HSV-1, HSV-2) and Cytomegalovirus (CMV), and histopathological analysis was used to detect signs of inflammation. The results were compared between subgroups organized according to gender, age, location of the samples, surgical approach, preoperative C-reactive protein (CRP), preoperative and 6 months postoperative Oswestry Disability Index (ODI) and Neck Disability Index (NDI), and Modic changes (MC) of the corresponding endplates. Also, we assessed the occurrence of postoperative infections within 6 months. RESULTS: Microbiological culture was positive in 38.78% of the analyzed intervertebral discs. Altogether, 180 bacteria were isolated. Coagulase-negative staphylococci (CONS) (23.41%) and Cutibacterium acnes (18.05%) were the most frequently detected microorganisms. None of HSV-1, HSV-2, or CMV were detected. Male patients (p = 0.00036) and cervical segments (p = 0.00001) showed higher rates of positive culture results. Ventral surgical approaches ( p < 0.001) and Type 2 MC (p = 0.0127) were significantly associated with a positive microbiological result ( p< 0.001). Neither pre- nor postoperative ODI and NDI are associated with positive culture results. In 4 (1.02%) patients, postoperative spondylodiscitis occurred. CONCLUSIONS: With 447 segments from 392 patients, we present one of the largest studies to date. While disc degeneration caused by HSV-1, HSV-2, and CMV seems unlikely, we found positive microbiological culture results in 38.78% of all discs. The role of local skin flora and sample contamination should be the focus of further investigations. LEVEL OF EVIDENCE: III. TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov (ID: NCT04712487, https://www. CLINICALTRIALS: gov/ct2/show/study/NCT04712487 ).

Long-Term Outcomes in Ventriculoatrial Shunt Surgery in Patients with Pediatric Hydrocephalus: Retrospective Single-Center Study.

OBJECTIVE: Long-term outcomes are rarely reported for patients with pediatric hydrocephalus. Ventriculoperitoneal shunting is the surgical standard; nevertheless, in selected patients, a ventriculoatrial shunt (VAS) remains an important alternative. This study aimed to analyze the causes of VAS revisions and complications. METHODS: Pediatric patients who underwent their first shunt operation between 1982 and 1992 were included. The timing, cause, and modality of VAS revisions were retrospectively determined. RESULTS: Overall, 138 patients were treated for hydrocephalus and 61 patients received a VAS during the follow-up period. A primary VAS was the first shunt type in 42 (68.85%) patients. In 19 (31.15%) patients, conversions to second-line VAS were carried out. The rates of VAS revisions performed for dysfunction or elective lengthening of a short atrial catheter were 52.2% and 22.9%, respectively. There was no difference in the number of VAS revisions between patients with primary VASs and second-line VASs. Age at VAS and etiology of hydrocephalus had no effect on the number of revisions. Specific VAS complications were observed in 2 patients. Deep positioning of the distal catheter led to asymptomatic tricuspid regurgitation that was reversible after shortening of the atrial catheter. Another patient presented with shunt nephritis and completely recovered after the atrial catheter was replaced with a peritoneal catheter. CONCLUSIONS: VAS remains an appropriate second-line alternative in selected patients. Specific VAS complications were rarely observed and completely reversible after treatment. However, regular and specific follow-up examinations are strongly recommended to avoid cardiopulmonary or renal complications.